The Tactical 12-Gauge is a combat shotgun with an extended breach capacity. It deals a great amount of damage with each shot and can easily obliterate opponents at close range. The double-barrel is better for maps with few bots, since there is no need for a large magazine, and therefore more time for the player to reload; however, on a well-populated or smaller map, the Tactical 12-Gauge comes into a league of its own, being able to cut eight players to ribbons before needing to reload. Of course, the 12-Gauge has the longest reload time of all weapons; this can be troublesome in a big firefight. It also fires four pellets like the shotgun.

The reloading on the shotgun is fairly unique among weapons; instead of loading a magazine of a set amount or rounds taking a set amount of time, human players reload the shotgun one round at a time directly into the breech. Although it takes longer to reload the entire magazine, you can fire instantly while reloading instead of having to wait (pressing the trigger stops the reload and fires a shot as long as there is at least one round in the weapon). Another tactic that can be used in TimeSplitters 2 for reloading this weapon is to switch to another weapon and switch back to the 12-Gauge; it instantly reloads it.

In TimeSplitters 2, The Tactical 12-Gauge has a secondary function in the form of two shells being fired directly after each other in one button press. Although in general, most bots have considerable resilience to even double-blasts. The blast creates more of a "knockback" or "stun" effect rather than being a direct damage weapon.

This weapon, like any shotgun, is not recommended for medium or long range engagements, as the buckshot is fired so the damage spreads over a wide area. However, if extremely necessary, the double blast increases the chance of immediate damage over long distances.

Maps such as Siberia or Streets are less then ideal for the Tactical 12-Gauge. Since there are large stretches of open land, there are few places where the Tactical 12-Gauge can be used efficiently. Smaller, more confusing maps make the Tactical 12-Gauge the dominant weapon. Maps such as the Bunker make for not only a dominant shotgun game, but a rather scary one too. Due to the large number of twists, turns, and narrow hallways, there is an incredible chance that a player's next turn may be their last.

In TimeSplitters Future Perfect, the weapon is exactly the same, albeit dropping the secondary fire. It also has a slightly longer recoil, leaving the player vulnerable for a larger period of time, however reload time is noticeably faster. Also, the appearance of the gun is dramatically different, adding wooden tones on some surfaces.

In TimeSplitters 2, the gun features a ammo stock designed to contain shells for easy use, which strangely houses only 7 of the shells the player has, on the final reload with correct aiming the player can see these rounds "disappear" as they are fed into the shotgun's breech. From a third-person view however, there are only 6 shells on the stock which never "disappear".

In Future Perfect, there are multiple categories of weapons (obviously). Generally speaking, how "good" a weapon is can be guessed based on how futuristic it is (and whether or not it is considered military-grade). The Tactical 12-Gauge is one of the exceptions to this rule, managing to prove itself to be far superior to the more futuristic Dispersion Gun in the shotgun category.

In Future Perfect, the reloading sounds are taken from the standard Shotgun in Second Sight, another Free Radical Design game.